1. Field of the Invention
The present invention relates to a 3D monitor, specifically to securing a frame of a half mirror which can control and maintain the angle of the half mirror of a 3D monitor.
2. Description of the Related Art
Generally, a 3D monitor is a device enabling people to view a 3D image using the difference between the images seen from right and left eyes respectively. Such a 3D monitor can be classified into two types, one using eyeglasses and the other being a lenticular type. The type involving eyeglasses can in turn be classified into types using polaroid glasses, LCD shutter glasses or ones using the principles of anaglyphs. However, wearing glasses to view 3D images is cumbersome for most people.
As for lenticular type, it can be classified into a direct vision type where lenticular lens sheets are placed on the surfaces of display devices such as a CRT or LCD, and projecting type where a projectors are used to project images on the lenticular lens sheet. Generally, half mirrors are installed in the lenticular type to transmit images.
An earlier 3D monitor comprises a first image display device installed on a lower portion of a case, a second image display device installed on the back of the case so as to be perpendicular to the first image display device, a half mirror forming a fort-five degree angle between the first and second image display device and a pair of securing frames supporting the half mirror.
The securing frames are installed on both sides of the case in a diagonal direction. Upper and lower end portions of the securing frames are locked onto the case by means of securing bolts. The securing frames are long and rectangular. A pair of engaging protrusions are formed on the inner sides of the securing frames, forming engaging grooves. Therefore, both ends of the half mirror are respectively inserted in the engaging grooves of the securing frames.
A pair of end caps are placed on the respective ends of the securing frames. Engaging grooves are respectively formed on the inner side of the end caps. Therefore, the half mirror inserted into the engaging grooves of the securing frames are secured by the end caps and at lower and upper ends.
However, when the half mirrors tilts away from the predetermined forty-five degree angle due to vibrations or external forces, it is difficult to correct the deviation. Also, since a gap of a predetermined length is formed between the engaging grooves of the securing frames and the half mirror, images can quiver when vibrations occur.